Gastro-intestinal cancers are a leading cause of mortality and account for 23% of cancer-related deaths worldwide. In order to improve outcomes from these cancers, novel tissue characterisation methods are needed in order to facilitate accurate diagnosis.
Rapid evaporative ionisation mass spectrometry (“REIMS”) may be used for the real time identification of tissues, e.g., during surgical interventions. Coupling of mass spectrometry with a surgical diathermy device has resulted in a sampling technology which has an intra-operative tissue identification accuracy of 92-100%.
This sampling technology allows surgeons to more efficiently resect tumours intra-operatively through minimizing the amount of healthy tissue removed whilst ensuring that all the cancerous tissue is removed.
Rapid evaporative ionisation mass spectrometry analysis of biological tissue has been shown to yield phospholipid profiles showing high histological and histopathological specificity similar to Matrix Assisted Laser Desorption Ionisation (“MALDI”), Secondary Ion Mass Spectrometry (“SIMS”) and Desorption Electrospray Ionisation (“DESI”) imaging. A mass and/or ion mobility spectrometric signal is obtained by subjecting the cellular biomass to alternating electric current at radiofrequency which causes localized Joule-heating and the disruption of cells along with desorption of charged and neutral particles. The resulting aerosol or surgical smoke is then transported to a mass spectrometer and/or ion mobility spectrometer for on-line mass and/or ion mobility spectrometric analysis.
The known rapid evaporative ionisation mass spectrometry technique is typically performed on external tissues or tissues accessed through surgery.
It is desired to provide an improved method of and apparatus for rapid evaporative ionisation mass spectrometry.